Underwater pool lights are used to enhance the beauty of swimming pools and make their usage during darkness safer and more aesthetically desirable. Since the light bulb producing the light normally is below the water level, it must be sealed in an enclosure to prevent contact with the pool water. When the light bulb in such underwater enclosure fails, the water level in the pool either must be lowered below the light enclosure so that a dry installation can be made or the enclosure must be moved above the water. Removable bulb enclosures exist, however the sealing gaskets heretofore employed therein are a continual problem since they tend to have many parts, are expensive, and when water inevitably leaks into the area about the light bulb, it is turned into steam which can generate pressure high enough to fail the structure sometimes by shattering the lens of the enclosure and blowing the glass from the lens into the pool. This has a tendency to cause personal injury. Also, the extra force required for failure often is provided by an adjacent swimmer.
When such enclosures are installed in pools having vinyl pool liners, the vinyl pool liner tends to become stretched and develop holes or breaks, resulting in leakage of pool water and the requirement for replacement. Vinyl liners are expensive, costing approximately $1500, and damage thereto is difficult and expensive to repair.
Therefore there has been a need for a pool light mounting structure which can be constructed relatively economically, is capable of relieving any steam pressure which might build up from the bulbs heat without generating a reverse leakage path, which can be constructed economically and easily from sheet metal rather than castings or moldings, and which is adaptable not only to traditional concrete and Gunite pools but also vinyl lined pools.